Background: Dental caries is a multifactorial disease with varying clinical picture and its diagnostic criteria is complicated, when initial lesion is considered. Hence, there is a need for an index which measures cavitated, non-cavitated, and initial lesion in dental caries. So, the purpose of this study was to compare the of def index with Nyvad's new diagnostic criteria.
Materials and Methods: A total of 249 school children in the age group of three to six years were selected for the study from Sajjan Rao School at Bangalore city. Children teeth were cleaned and dried with cotton rolls and chip blower. The dental caries examinations were conducted under standardized conditions using plane mouth mirrors and explorers with the help of artificial illumination. The diagnostic criteria used were deft and d, e, and f component of Nyvad's new caries diagnostic criteria. Mann Whitney 'U' test was used to compare the two indexes at five percent significant level.
Results: The mean value for deft was 2.48 and the mean for d, e, and f component of Nyvad's new caries diagnostic criteria was 3.18 which shows statistically significant difference with P value of <0.05.
Conclusion: The result obtained by Nyvad's new caries diagnostic criteria produces values much higher than those with def caries index system. Hence, Nyvad's new caries diagnostic criteria can be used to diagnose dental caries at the initial stages, which in turn will reflect exact prevalence of caries.